PHYSIOLOGY OF THE COROLLA. 19/ 



side petals ; and carina^ f. iGG, the keel, consist- 

 ing of two petals, united or separate^ embracing 

 the internal organs,^! l67. In Trifoliiim all the 

 petals are sometimes united into one at the lower 

 part. 

 bicompkta, incomplete, when parts, which analogy 

 would lead us to expect, are delicient, as in 

 Amorpha^ a papilionaceous flower apparently, but 

 ^ consisting of the vexillum only ; or Rittera of 

 Schreber,y! 168, a rosaceous one with a single 

 lateral petal, seeming as if four others had been 

 stripped oti*. 

 It is remarkable that irregular flowers sometimes 

 vary to regular ones on the very same plant, as 

 in Bignonia radicans^ Curt. Mag. z^. 485 ; and 

 Antirrhinum Linaria,f. 169, Engl. Bot. t. 658 

 and 260. 

 Linnaeus was of opinion that the Corolla originated 

 from the Liber or inner bark, as the Calyx from the 

 outer, but this cannot be defended now the real phy- 

 siology of the bark is better understood. 



The whole use and physiology of the Corolla have 

 not yet been fully explained. As a protection to the 

 tender and important parts within, especially from wet, 

 its use in many cases is obvious, but by no means in 

 all. Linnasus imadned it to serve as winjzs, to waft 

 the flower up and down in the air, and so to promote 

 the functions of the Stamens and Pistils, as will here- 

 after be described ; nor is this opinion unfounded. 



